What I want to do is to HTTP basic authenticate without seeing that pop-up dialog box (with realm, username, password).
I think that I need to send some headers to the server from the browser, but i dont know how to send HTTP header from JScript sau HTML.
Does anyone know how to do that?

So whats u'r problem? just make a simple form, "on submit" it will send your info to another page, which will proccess it...

I believe he wants to make a form log into an htaccess protected directory instead of having that default 'security box' show up.

It's somewhat possible. You can make the form values redirect with javascript to userassword@site.com, but Internet Explorer has disabled this feature because of security problems. To make it work in IE you'd need to install a patch.

Impossible with HTML...

username : password@domain.com no longer works and even if a patch exists how many of your visitors are going to have it...Or be bothered to get it to just view your site...

You need to move on...Try PHP...PHP is the future

If you need any help with PHP just ask

-James